The ferroelectric and piezoelectric properties of (Hf 1−x Ce x )O 2 films on indium tin oxide/Pt/TiO x /SiO 2 /(100)Si substrates obtained using a no-heating radio-frequency magnetron sputtering deposition method

The effect of composition and film thickness on the ferroelectric and piezoelectric properties of (Hf 1− x Ce x )O 2 films deposited without substrate heating was investigated. (Hf 1− x Ce x )O 2 films with various x values ( x = 0.07–0.27) and thickness (150–880 nm) were deposited via RF magnetron sputtering on indium tin oxide (ITO)/Pt/TiO x /SiO 2 /(100)Si substrates. The crystalline phases of the films were observed by X-ray diffraction. The measurements of electrical properties revealed ferroelectric phases in the x range of 0.11–0.21. The film with x = 0.16 exhibited the maximum remanent polarization (Pr) of 15 μ C cm −2 , as well as the highest effective piezoelectric coefficient. In addition, the ferroelectric and structural properties remained almost unchanged with increasing film thickness. Therefore, the no-heating deposition of ferroelectric (Hf 1− x Ce x )O 2 films and their phase stability with respect to thickness were demonstrated in this study. This work provides a pathway for the deposition of ferroelectric (Hf 1− x Ce x )O 2 films on flexible, wearable sensors.